JP2010031446A - Method for producing dyed woven and knit fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing dyed woven and knit fabrics by dyeing processing fabrics made by weaving and knitting a false twisted yarn capable of bringing dyed quality of the woven and knit fabric by weakening periodic color concentration difference inherited to the dyed woven and knit fabric made of a superfine filament false twisted yarn and improving the color difference into an almost invisible level. <P>SOLUTION: The method for producing the dyed woven and knit fabric by dyeing processing the fabric made by weaving and knitting a false twisted yarn is provided. The false twist-processed yarn has a monofilament fineness of not more than 0.8 [dtex], comprises polyester multi-filaments selected from polyethylene terephthalates, polytrimethylene terephthalates, polybutylene terephthalates and polyethylene isophthalates, and is a drawn yarn untreated by fluid entangling. The method for producing the dyed woven and knit fabric is (a) to bring spaces between or among two or more discharge holes installed in a spinneret to be large, (b) to bring the arrangement of the discharge holes to have high air penetration or (c) to shorten the distance from the discharge surface of the spinneret to a position to which air-cooled air is blown so that the yarn has a CV value of digitized 5,000 data not more than 1.0[%] when the false twist-processed yarn is dyed in a dyeing tank in which a blue color official approval dye and a dispersing agent are dissolved in water and which is held at 95°C and the variance of the dyed concentration in the fiber axial direction of the yarn is measured by an FYL analyzer, or the yarn has a maximum value in 3-30 m power spectrum wavelength obtained by the Fourier analysis of digitized data measured by the FYL analyzer not more than 25[-]. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for producing a dyed woven or knitted fabric obtained by dyeing a fabric obtained by knitting or knitting false twisted yarn. More specifically, the present invention provides a uniform appearance when used in a woven or knitted fabric with less variation in dye density in the fiber axis direction. The present invention relates to a method for producing a dyed woven or knitted fabric obtained by dyeing a fabric obtained by knitting or knitting false twisted yarn composed of ultrafine filaments.

  False twisting is widely used as the most rational means of bulking thermoplastic synthetic fiber multifilaments. False twisted yarns made of ultrafine filaments used in the sports clothing field are also on the market. In recent years, high-speed drawing simultaneous false twisting yarn using a friction false twisted twisted body has also been developed from the viewpoint of cost pursuit. Extra-fine filaments need to be provided with many discharge holes in a fixed spinneret area in the melt spinning process, and the penetration of the air when the polymer is melt-discharged and then air-cooled is poor, and thinning phenomenon directly under the spinneret is not good. Since it tends to be uniform, there is a problem that periodic fineness spots tend to occur in the fiber axis direction (so-called resonance periodic spots).

  When the false twisted yarn obtained by co-stretching false twisted yarns of highly oriented unstretched multifilaments composed of ultrafine filaments having periodic fineness irregularities in the fiber axis direction is evaluated by cylindrical knitting dyeing, Differences in density (called tiger stripes, band stripes, etc.) are produced. In particular, in the case of high-speed simultaneous simultaneous false twist using a friction false-twisted twisted body, the simultaneous draw-stretching is performed by adding the set draw ratio to the fineness unevenness period of the highly oriented unstretched multifilament in twisting and untwisting tension. Variations in the periodicity clearly occur, and the dyed cylinder knitted fabric obtained from the processed yarn exhibits a strong periodicity difference that substantially matches the twisting and untwisting tension variations.

  Highly oriented unstretched multifilament cycles can result in unsightly streaks and streak problems when dyed woven knitted products are obtained using false-twisted yarns that show a strong periodic shading difference in the tubular knitted fabric. Although the conditions of the melt spinning process are set in order to reduce the unevenness of the fineness, there are many ultra-fine filament false twisted yarns that are produced within an acceptable range of woven and knitted products that are not allowed to have severe streaks and shade differences. is there.

  The present invention is intended to solve the above-mentioned problems, and reduces the periodic shading difference of dyed woven or knitted fabric of false-twisted yarn of ultrafine filaments, and improves it to a level that is almost invisible. It is an object of the present invention to provide a method for producing a dyed woven or knitted fabric obtained by dyeing a fabric obtained by knitting or knitting false twisted yarn capable of uniform dyeing quality.

Means for solving the above-mentioned problem, that is, the first of the present invention is a method for producing a dyed woven or knitted fabric obtained by dyeing a fabric obtained by knitting or knitting false twisted yarn. It is a drawn yarn having a fiber fineness of 0.8 [dtex] or less and comprising a polyester multifilament selected from polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, and polyethylene isophthalate, and is not subjected to fluid entanglement treatment, When the false twisted yarn was dyed in a dyeing tank in which a blue hue test dye and a dispersant were dissolved in water and maintained at 95 ° C., and the dispersion of the dye density in the fiber axis direction of the yarn was measured with an FYL analyzer, it was digitized (A) Each of a plurality of discharge holes provided in the spinneret so that the CV value of 5000 pieces of data is 1.0 [%] or less. The interval is widened, (b) a discharge hole arrangement with high wind penetration, or (c) the distance from the spinneret discharge surface to the point where air is sent by air cooling is shortened. This is a method for producing a dyed woven or knitted fabric.
The second is a method for producing a dyed woven or knitted fabric obtained by dyeing a fabric obtained by knitting or knitting false twisted yarn, wherein the false twisted yarn has a single fiber fineness of 0.8 [dtex] or less, and It is a drawn yarn that is made of a polyester multifilament selected from polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, and polyethylene isophthalate, and has not been subjected to fluid entanglement treatment.The false twisted yarn is treated with a blue hue test dye and a dispersant. Power spectrum obtained by Fourier analysis of digitized data when dyed in a dyeing tank dissolved in water and kept at 95 ° C. and measured with a FYL analyzer the periodicity of fluctuations in dye density in the fiber axis direction (A) It is provided in the spinneret so that the maximum value within the range of 3 to 30 m is 25 [−] or less. Increase the interval between several discharge holes, (b) use a discharge hole arrangement that increases the wind penetration, or (c) shorten the distance from the spinneret discharge surface to the point where air is sent by air cooling. This is a method for producing a dyed woven or knitted fabric.
Thirdly, the false twisted yarn is dyed in a dyeing tank in which a blue hue test dye and a dispersant are dissolved in water and maintained at 95 ° C., and the periodicity of the fluctuation of the dye density in the fiber axis direction of the yarn is measured with an FYL analyzer. In the method for producing a dyed woven or knitted fabric according to the first aspect, the maximum value in the wavelength range of 3 to 30 m of the power spectrum obtained by Fourier analysis of the digitized data is 25 [−] or less. is there.
The fourth is a method for producing a dyed woven or knitted fabric according to any one of the first to third aspects, wherein the filament constituting the false twisted yarn has a single fiber fineness of 0.4 [dtex] or less.

  The present invention is a woven or knitted product made of false twisted yarns composed of ultrafine filaments, and it was produced as an acceptable range of shade differences that were not visible to streaks and streaks. By using a false twisted yarn that has passed an extremely strict evaluation standard for the degree and / or periodicity, a very uniform dyeing quality can be imparted to the woven or knitted fabric. It is suitable as a woven or knitted fabric for sports apparel and women's apparel, and provides a soft, beautiful and uniform dyeing quality.

The preferable example of the graph (spectrogram) drawn when calculating | requiring the maximum value in the wavelength 3-30m of the power spectrum obtained by Fourier-analyzing the data which measured the digitized yarn used by this invention with the FYL analyzer and digitized it is shown. An unfavorable example of a graph (spectrogram) drawn when obtaining a maximum value within a wavelength of 3 to 30 m of a power spectrum obtained by Fourier-analyzing data obtained by measuring a false twisted yarn used in the present invention with an FYL analyzer. .

  The thermoplastic synthetic fiber multifilament referred to in the present invention is a multifilament made of a polymer having thermoplasticity, and refers to polyester. Specific examples include polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, and polyethylene isophthalate. These may contain a small amount of a polymer, an antioxidant, an antistatic agent, a pigment, a matting agent, a fluorescent brightening agent, a micropore forming agent, other additives, and the like. However, polyester is preferable, and polyethylene terephthalate is most preferable in stably melt-spinning multifilaments made of ultrafine filaments.

  The false twisted yarn used in the present invention is false twisted into a multifilament obtained by spinning the thermoplastic synthetic polymer as described above. The single fiber fineness of the filament constituting the false twisted yarn needs to be 0.8 [dtex] or less. When the single fiber fineness is larger than 0.8 [dtex], it becomes difficult to satisfy the water pressure resistance of the fabric for sports clothing, and the texture is hard, which is not preferable. More preferably, it is 0.4 [dtex] or less. However, if the fineness of the single fiber is too small, yarn breakage during false twisting and fuzz of false twisted yarn increase, and the knitting property deteriorates. Therefore, it is preferably 0.1 [dtex] or more.

  The false twisted yarn used in the present invention was measured with an FYL analyzer, and the digitized CV value of 5000 pieces of data was 1.0% or less, or the data measured with the FYL analyzer was obtained by Fourier analysis. It is necessary that the maximum value within a wavelength of 3 to 30 m of the power spectrum is 25 [−] or less.

  The FYL analyzer is a device that continuously measures the dye density in the direction of the fiber axis of the yarn. The analog data can be converted into digital data by a commercially available AD converter and recorded on a personal computer. The small CV value of 5000 data means that the variation in the dye density in the fiber axis direction of the yarn is small. (Detailed measurement method will be described later.) The CV value of commercially available ultrafine filament false twisted yarn is often about 1.5 [%]. Although it depends on the level of the power spectrum described later, if the processed yarn having a CV value of 1.5 [%] is evaluated by cylindrical knitting dyeing, it will not be a strong shade difference that seems to be regarded as a defect at first glance, If you look seriously, you can see that there is a slight contrast. When this false twisted yarn having a CV value of 1.5% is used as a weft of a woven fabric and dyeing is performed after weaving, it is not so bad that it is taken to the fault, but it is not preferable because it feels a slight stripe or streak difference. . A processed yarn having a CV value larger than 2.0 [%] has a strong shading difference at a glance, and fails. Of course, when it is used for textiles, it becomes a defect of streaks and stripes and is judged as a rejected product. When the CV value is 1.0 [%] or less, even if the dyed tube knitted fabric is viewed seriously, there is no difference in shading. It becomes a preferable uniform thing which does not feel the difference of light and shade.

  On the other hand, if analog data measured with an FYL analyzer is converted into digital data with an AD converter and integrated in a personal computer, a power spectrum is obtained by performing Fourier analysis using commercially available software. A small power spectrum at a specific wavelength (yarn length) means that the periodicity of the dye density variation in the fiber axis direction is weak. A problem peculiar to ultrafine filaments is that periodic fineness spots are likely to occur due to poor cooling when melted and discharged from the discharge holes and air-cooled. The periodicity which becomes a problem when false twisting is performed after stretching an unstretched multifilament or simultaneously with stretching depends on the spinning speed and the stretching ratio, but is on the 3-30 m level. If the maximum value of the power spectrum within the wavelength range of 3 to 30 m is 25 [−] or less, the dye density fluctuation is less likely to appear periodically, and as a result, it is difficult to feel stripes on the dyed cylinder knitted fabric or dyed fabric, which is preferable. . If the power spectrum is stronger than 25 [-], although depending on the CV value level, a striped shading difference appears slightly on the dyed fabric used for the dyed tube knitted fabric and the weft, which is not preferable. If the power spectrum is stronger than 30 [-], depending on the CV value level, dyed fabrics used for wefts often fail due to fringe defects. FIG. 1 shows a graph (spectrogram) in which the horizontal axis indicates the wavelength and the vertical axis indicates the power spectrum. However, there is no portion where the power spectrum indicates 25 [−] or more within the wavelength range of 3 to 30 m. It is an example at the time of measuring a preferable false twisted yarn. FIG. 2 shows a spectrogram obtained by measuring another false twisted yarn. The power spectrum exceeds 25 [−] and is about 33 [−] at a wavelength of about 12 m, which is preferable in the present invention. There is nothing.

  The false twisted yarn satisfying both the CV value of 1.0 [%] or less and the power spectrum of 25 [−] or less is satisfactory in the uniformity of the dyed woven or knitted fabric, and is a very preferable processing. It is a thread.

  The false twisted yarn used in the present invention is preferably obtained by simultaneously drawing an undrawn multifilament with a false false twisted twisted body. From the viewpoint of high-speed productivity, the simultaneous drawing of undrawn multifilament with a false false twisted twisted body is excellent and effective in reducing costs.

  The total fineness of the false twisted yarn used in the present invention is preferably about 10 [dtex] to 300 [dtex]. In addition, the cross-sectional shape of the multifilament supplied to false twisting is not limited to the usual round cross-section, but also multi-leaf cross-section, polygonal cross-section, flat cross-section, hollow cross-section, special deformed cross-section, etc., spinning operability, false twist operation Anything is applicable as long as it does not harm sex. In many cases, the cross section of the filament constituting the false twisted yarn has undergone cross section deformation due to contact between the filaments due to torsion deformation. The crimp characteristics of the false twisted yarn are different depending on whether the first-stage heater false-twist or the second-stage heater is stabilized, but the crimp expression rate according to the method described later is preferably 5 to 60 [%].

  Although the method of manufacturing the false twisted yarn used in the present invention is not particularly limited, an example will be described. The false twisted yarn used in the present invention can be obtained by spinning a thermoplastic synthetic polymer in a melt spinning facility and performing false twisting after stretching, or by simultaneous false twisting. It is necessary that the single fiber fineness of the filament constituting the false twisted yarn is 0.8 [dtex] or less. In order to reduce the FYL data CV value of false twisted yarn and reduce the maximum value within the 3 to 30 m wavelength of the power spectrum, in the melt spinning process, the thinning phenomenon of melted and discharged filaments is made uniform and unstretched It is important to reduce periodic fineness spots in the fiber axis direction of the multifilament. It is preferable that the unstretched multifilament has a URI value of 2.5 [%] or less according to the measurement method described later, and has a weak power spectrum at a wavelength portion of about 2 to 20 m. For this purpose, it is effective to widen the intervals between the plurality of discharge holes provided in the spinneret and to form a discharge hole array that enhances air penetration. It is also effective to shorten the distance from the spinneret discharge surface to the point where the air-cooled wind is sent, and the wind speed is preferably increased to such an extent that the spinning operability is not impaired. However, if the spinneret discharge surface is cooled and the temperature is lowered, the operability and mechanical properties of the unstretched multifilament will be impaired. Use a heater that keeps the spinneret warm as necessary, and keep the wind direction constant. A device such as providing such a current plate is effective. The unstretched multifilament is wound by applying an appropriate oil agent as uniformly as possible.

  In the case of false twisting after drawing an undrawn multifilament to obtain a drawn yarn, the spinning speed is not particularly limited, and the winding is performed at 1000 to 4000 [m / min]. The unstretched multifilament after spinning and winding is appropriately stretched at a temperature near the glass transition temperature to become a stretched multifilament. It is possible to appropriately adjust the heat shrinkage rate by performing heat setting during stretching. After spinning and drawing are continued to obtain a drawn yarn, false twisting may be performed. When undrawn multifilaments are drawn simultaneously with false twisting, it is not preferable that the yarn is too slow from the viewpoint of the threading property at the time of drawn simultaneous false twisting and the change over time of the undrawn multifilament, and spinning at 1800 to 4000 [m / min]. Winding speed is preferred. For the false twisted body, pin spindle type, swirl flow air nozzle type, friction false twisted twisted body type (3-axis circumscribed friction false twist type, cross belt type nip false twist type) etc. can be used. From the viewpoint, it is preferable to stretch and false-twist unstretched multifilaments using a friction false twisted twisted body. The false twisting may be performed by a one-stage heater or may be stabilized by two-stage heater false twist. The yarn temperature at the outlet of the first stage heater (false twist heat fixing heater) is slightly different depending on the type of polymer and false twisting of the drawn yarn and simultaneous drawing of the undrawn yarn. C.] degree is preferable. When stabilizing using a second stage heater (residual torque reduction, crimped stabilizer heater), set the temperature of the second stage heater to about 160 to 220 [° C] and set the feed rate of the second stage heater zone. A relaxed state of about 5 to 20% is preferable. The number of false twists during false twisting depends on the type of polymer, but in the case of a pin spindle type, the number of false twists [T / m] × √worked yarn dtex is preferably about 2600-34000. Fluid entanglement treatment after false twisting and before winding is preferred from the viewpoints of preventing winding shape defects, improving false twisting of false twisted yarn, and improving ease of handling in subsequent steps. By properly oiling before winding, unwinding and handling in the subsequent process are improved.

  The false twisted yarn obtained as described above is knitted and woven into a fabric and dyed. The false twisted yarn is subjected to actual twisting, oiling, sizing, etc. as necessary, and then knitted or woven. The false twisted yarn may be used by being mixed with other yarns by a method such as blending, twisting, blending, knit, or weaving. The woven or knitted fabric is dyed according to its use. For example, in the case of sports clothing fabrics, relaxation, pre-setting, dyeing, and final setting are performed, but calendering may be performed before or after dyeing. If necessary, special functionalities such as moisture permeability and water repellency, water repellency, moisture absorption exothermicity can be imparted by laminating, coating, padding and the like. In the case of women's apparel polyester fabric use, it is preferable to soften the texture by performing an alkali weight reduction treatment before dyeing. After dyeing, an antistatic agent or the like is appropriately applied and final set is performed to obtain a dyed fabric.

  Hereinafter, specific examples will be described. In addition, the measuring method of each characteristic value used in this invention was based on the following.

(FYL analyzer measurement)
An FYL-500SR apparatus manufactured by Toray Engineering Co., Ltd. is used. Basically, prepare the dyeing tank and washing tank according to the instruction manual. In the dyeing tank, 1 kg of a designated dye (Toray Blue) or a blue hue test dye equivalent thereto and 200 g of a dispersant (Sun Salt WA, manufactured by Nikka Chemical Co., Ltd.) is added to about 30 liters of water, and the temperature is kept at 95 ° C. The washing tank is filled with water and kept at 85 ° C. The washing tank is always filled with fresh water and is gradually replaced by overflow. The sample processed yarn is put on a creel, unwound and guided to a dyeing tank. The angle of the Nelson roller is adjusted as appropriate so that the yarn-thread contact on the Nelson roller in the dyeing tank does not occur, and the sample processed yarn is wound 45 times by the Nelson roller. The sample processed yarn is guided from the dyeing tank to the cleaning nozzle and then to the cleaning tank. The angle of the Nelson roller is appropriately adjusted so that the yarn-thread contact on the Nelson roller in the washing tank does not occur, and the sample processed yarn is wound seven times on the Nelson roller. The sample processed yarn is sequentially guided from the washing tank to the draining nozzle and draining spindle, and then to the measuring unit. The pressure regulating valve of the washing nozzle is adjusted to set the pressure to 1.0 [kg / cm ² ]. The pressure regulating valve is also adjusted for the draining nozzle and set to 1.2 [kg / cm ² ]. For the measurement unit, a standard sample (white 100 [%] and blue 40 [%]) is run at 30 [m / min] in advance, and the FYL [%] data level is set.

The sample processing yarn led from the draining nozzle to the measuring section makes a yarn path according to the instruction manual. From the knot detection end, pass through the false twisting part, lead to the colorimetric part, and take it out with the ejector through the roller. Adjust the pressure regulating valve of the ejector to 1.5 [kg / cm ² ].

  In normal FYL measurement, data is output using the attached output part. In the present invention, the FYL colorimetric analog signal is output using an AD converter and a Windows '98 installed personal computer. The AD converter uses NR-2000 manufactured by Keyence Corporation, and the attached software is installed in the personal computer. Also, Microsoft Excel '98 software is installed on the personal computer. Connect the wiring from the AD converter to a personal computer using a dedicated PC card. Adjust the zero point of the AD converter by operating the computer. Two FYL analog data signal lines are led to an AD converter, and the analog voltage signal is converted into digital data so that it can be integrated in a hard disk of a personal computer.

  The FYL analyzer is operated at a speed of 30 [m / min] if the setting of the yarn path of the sample processed yarn from the creels to the ejector, the AD converter, and the personal computer can be set. By operating the personal computer, the digital voltage data sampling frequency is set to 2.67 [Hz] (data sampling every 375 [milliseconds]), the number of measurements is set to the single mode, and the sampling number is set to 5000. Since the sample processed yarn is run and stays in the dyeing tank for a while, and there is a deeply dyed part that has been dyed for a long time, look at the FYL [%] data analog meter of the FYL analyzer and wait until it becomes stable . (FYL [%] data in the dark-dyeing portion shows a low value.) When the yarn continuously sent to the dyeing tank passes through the color measurement portion, the FYL [%] data rises to a high value. After confirming that it is stable, operate the personal computer to perform digital voltage data sampling. The sampled digital voltage data [V] is stored in the hard disk of the personal computer (extension is .ndh).

(Calculation of CV value)
extension. from ndh. To be able to finally calculate with Microsoft Excel '97 via csv. Convert to xls. Microsoft Excel '97 is started, the average value and population standard deviation of the collected 5000 sampling digital voltage data [V] are calculated, and the CV value is obtained by the following equation.
CV value [%] = {(population standard deviation) / (average value)} × 100

(Calculation of power spectrum maximum value)
The digital sampling voltage data [V] is once every 0.1875 [m] of yarn length. Therefore, the yarn length corresponding to 5000 sampling corresponds to 937.5 [m]. Among these data, power spectrum analysis is performed for the first to 4096th sampling (yarn length 768 [m]). Perform Fourier analysis in the analysis tool of Microsoft Excel '97. The Fourier analysis data is a complex number, but the absolute value of the complex number is obtained using the function IMABS in Microsoft Excel '97, and the first to 4096th power spectrum data is obtained. The wavelength [m] is calculated by Microsoft Excel '97 from each measured yarn length. The first sampling data corresponds to a yarn length of 0.1875 [m], and the 4096th data corresponds to a yarn length of 768 [m].
Wavelength [m] of sampling nth time = 144 / yarn length [m] of sampling nth time = 144 / (0.1875 [m] × n)
Accordingly, the first wavelength at the start of sampling is 768 [m], the second is 384 [m], the third is 256 [m], and when calculated sequentially, the 4096th wavelength is 0.1875 [m]. Wavelength data [m] on the horizontal axis, power spectrum data [-] on the vertical axis, 3 to 30 [m] on the horizontal axis, and an appropriate scale of 0 [-] or more on the vertical axis A graph like this is obtained. The power spectrum maximum value [−] in the horizontal axis (wavelength) 3 to 30 [m] is read. For example, in the example of FIG. 1, the maximum value of the power spectrum is 13.3 [−], which is preferable as the false twisted yarn used in the present invention.

(Entanglement)
A sample processed yarn of an appropriate length is taken out and suspended vertically by applying a load of 1/10 [cN / dtex] to the lower end. Next, an appropriate needle is taken out into the sample processed yarn, and the distance [mm] to which the needle moves until the load is lifted slowly is measured 20 [times] to obtain an average value L [mm]. The degree of entanglement is calculated by the following formula.
Degree of confounding [ke / m] = 1000 / (2 × L)

(Crimp expression rate)
A wrap reel with an appropriate frame circumference is used to make an 8-turn cassette under a load of 1/10 [cN / dtex]. Immerse in boiling water for 5 minutes under no load. A sample is taken out from boiling water, and a load of 2/10 [cN / dtex] is applied in a wet state to measure the length m [cm] of the case after 1 minute. Next, the load is removed, the water is lightly drained, and then dried in an oven at 60 [° C.] for 30 minutes. The yarn is taken out from the oven, allowed to cool for 1 hour, a load of 2/1000 [cN / dtex] is applied, and the length n [cm] of the case after 1 minute is measured. The measurement is repeated 5 times, and average values M [cm] and N [cm] for m [cm] and n [cm] are obtained. Crimp expression rate [%] is calculated by the following equation.
Crimp expression rate [%] = {(MN) / M} × 100

(URI value)
Measured by an inert test using a Worcester Evenestester 3 manufactured by Zerbegger Worcester. A slot is selected by multifilament denier, measured for 2 minutes at a yarn speed of 50 m / min while applying false twist, and a chart is drawn. At that time, adjust so that the average denier of the multifilament is drawn in the center of the chart. When the maximum value of the obtained chart is A [%] and the minimum value is B [%], the URI value is calculated by the following equation.
URI [%] = AB

(Periodicity of fineness spots)
Using a Worcester Evenestester 3 manufactured by Zerbegger Worcester, the normal test is used. A slot is selected with multifilament denier, measured for 10 minutes at a yarn speed of 50 m / min while applying false twist, and a spectrogram is drawn with the attached power spectrum analyzer. If there are periodic fine spots, a wavelength portion with a high power spectrum appears.

Example 1
A polyethylene terephthalate semi-dal chip having an intrinsic viscosity of 0.62 is melted and discharged from a spinneret in which 72 [single] round discharge holes are arranged on the outer peripheral surface diameter of the nozzle of 66 [mm] using a melt spinning facility. Air cooled at a wind speed of 0.45 [m / sec] from a point 20 [mm] below the discharge surface, and after applying the oil agent, wound on a godet roller rotating at 2400 [m / min], and continuously stretching heat It was set to obtain a polyethylene terephthalate drawn multifilament of 56 [dtex] / 72 [filament]. The drawn multifilament had a URI value of 1.5 [%], and the periodicity seen in the spectrogram of the Wooster Eve Tester was weak. The drawn multifilament was false-twisted with a one-stage heater using a TH-312 type pin spindle type false twister manufactured by Aiki Seisakusho. The false twisting speed was 120 [m / min], the false twist number was 4000 [T / m], the heater temperature was 190 [° C.], and the feed rate was adjusted so that the twisting tension was 6 [g]. The obtained false twisted yarn had a crimp expression rate of 41 [%], measured with an FYL analyzer, and the digitized CV value of 5000 data was 0.74 [%], and a power spectrum obtained by Fourier analysis. The maximum value within the wavelength range of 3 to 30 m was 13.0 [−]. When the false twisted yarn was subjected to cylindrical knitting test dyeing, it was preferable that no slight difference in stripes and streaks was observed even though there was some irritation. Sizing and warping 56 [dtex] / 72 [fil] polyethylene terephthalate semidal drawn multifilaments for warp, using the false twisted yarn as weft, warp density 149 [in / inch], weft density 112 [in / Inch] was plain woven to obtain a high-density taffeta fabric. By a conventional method, relaxation, presetting, dyeing, and calendering were performed to obtain a dyed fabric. The dyed fabric was soft and satisfactorily satisfied with the water pressure resistance for sports apparel use, and it was a uniform and preferred one that did not feel streaks and stripes due to dye density spots in the fiber axis direction of the weft.

(Comparative Example 1)
A drawn multifilament (56 [dtex] / 48 [fil]) was obtained in substantially the same manner as in Example 1 except that the spinneret was changed to a spinneret having a number of die discharge holes of 48 [ke]. The URI value was 1.4 [%] and the periodicity was weak. A false twisted yarn was obtained in substantially the same manner as in Example 1. The false expression rate of the false twisted yarn is 48 [%], the CV value of 5000 data measured with an FYL analyzer is 0.70 [%], the wavelength 3 of the power spectrum obtained by Fourier analysis The maximum value in ˜30 m was 11.4 [−]. When a dyed tube knitted fabric and a dyed fabric were obtained in the same manner as in Example 1, the dyeing uniformity was excellent, but the soft feeling and the water pressure resistance as a sports clothing fabric were not satisfactory.

(Example 2)
A polyethylene terephthalate semi-dal chip having an intrinsic viscosity of 0.62 is melted and discharged from a spinneret in which 72 [single] discharge holes are arranged on the outer peripheral surface diameter of the nozzle of 66 [mm] using a melt spinning facility, and the spinneret discharge surface Air-cooled at a wind speed of 0.45 [m / sec] from a point 20 [mm] below, and after applying the oil agent, unstretched multifilament 2 obtained from two adjacent spinnerets at 2400 [m / min] The books were aligned and taken as 80 [dtex] / 144 [fil]. The URI value of the unstretched multifilament taken up was 2.0 [%] and the periodicity was weak. A three-stage heater drawing and simultaneous false twisting were performed with a TH-312 pin spindle type false twisting machine manufactured by Aiki Seisakusho to obtain false twisted yarn. The number of false twists was 4200 [T / m], the draw ratio was 1.47 times, and the heater temperature was 170 ° C. The false twist rate of the false twisted yarn is 35 [%], the CV value of 5000 data measured with an FYL analyzer is 0.94 [%], and the wavelength of the power spectrum obtained by Fourier analysis. The maximum value within 3 to 30 m was 17.0 [−]. As in Example 1, a dyed tube knitted fabric and a dyed fabric were obtained. The dyed fabric was more preferable in that the soft feeling and water pressure resistance of the dyed fabric of Example 1 were improved.

(Comparative Example 2)
In the melt spinning process of Example 2, the melt is discharged from a spinneret in which 144 [single] discharge holes are arranged on the outer peripheral surface diameter of 66 [mm], and one unstretched multifilament from one spinneret. Was taken as 80 [dtex] / 144 [fil], and an unstretched multifilament was obtained in the same manner as in the melt spinning step of Example 2. The URI value of the unstretched multifilament was 3.6 [%], and the periodicity for each wavelength (yarn length) of about 8 m was found in the spectrogram. The unstretched multifilament was simultaneously false twisted by one-stage heater stretching using an HTS-1500 triaxial circumscribed friction false twisting machine manufactured by Teijin Seiki. The heater temperature was adjusted so that the false twisting speed was 600 [m / min], the draw ratio was 1.47 times, and the yarn temperature at the heater outlet was 170 [° C.]. The twisted disk material is polyurethane, 4 sheets having a diameter of 9 [mm] and a diameter of 58 [mm] were used. The ratio of the twisted disk peripheral speed to the yarn speed was set to 1.8 times. When a tension meter was inserted into the untwisting zone, the data was digitized with an AD converter, collected on a personal computer, a power spectrum was obtained, and a spectrogram was drawn. As a result, fluctuations in the untwisting tension period of about 12 m were confirmed. The false twisted yarn obtained had a crimp expression rate of 31 [%], measured with an FYL analyzer, and the digitized CV value of 5000 data was 2.14 [%]. The power spectrum obtained by Fourier analysis was obtained. The maximum value within the wavelength range of 3 to 30 m was 31.5 [−]. The wavelength (yarn length) representing the maximum value of the power spectrum was about 12 [m]. Although the dyed cylinder knitted fabric of the false twisted yarn obtained is not obvious tiger stripes, it has a width and feels a difference in density, and the dyed fabric has an uneven and unfavorable feeling of stripes in the weft direction. It was a thing.

  Table 1 shows the conditions of Examples 1-2 and Comparative Examples 1-2, yarn physical properties, and evaluation results of the fabric.

  A very uniform dyeing quality can be imparted to the woven or knitted fabric, which is suitable as a method for producing a dyed woven or knitted fabric for sports clothing or women's clothing.

Claims (4)

A method for producing a dyed woven or knitted fabric obtained by dyeing a fabric obtained by knitting or knitting false twisted yarn,
The false twisted yarn has a single fiber fineness of 0.8 [dtex] or less, is made of a polyester multifilament selected from polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, and polyethylene isophthalate, and is subjected to fluid entanglement treatment. No drawn yarn,
When the false twisted yarn is dyed in a dyeing tank in which a blue hue test dye and a dispersant are dissolved in water and maintained at 95 ° C., and the variation in dyeing density in the fiber axis direction of the yarn is measured with an FYL analyzer, digitization is performed. (A) Widen the intervals between the plurality of ejection holes provided in the spinneret so that the CV value of the 5000 pieces of data is 1.0 [%] or less, (b) High wind penetration A method for producing a dyed woven or knitted fabric, characterized in that a discharge hole arrangement is used, or (c) a distance from a spinneret discharge surface to a point where air is cooled is sent. A method for producing a dyed woven or knitted fabric obtained by dyeing a fabric obtained by knitting or knitting false twisted yarn,
The false twisted yarn has a single fiber fineness of 0.8 [dtex] or less, is made of a polyester multifilament selected from polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, and polyethylene isophthalate, and is subjected to fluid entanglement treatment. No drawn yarn,
When the false twisted yarn was dyed in a dyeing tank in which a blue hue test dye and a dispersant were dissolved in water and maintained at 95 ° C., and the periodicity of the dye density variation in the fiber axis direction of the yarn was measured with an FYL analyzer (A) Each of a plurality of discharge holes provided in the spinneret so that the maximum value in the wavelength range of 3 to 30 m of the power spectrum obtained by Fourier analysis of the digitized data is 25 [−] or less. The interval is widened, (b) a discharge hole arrangement with high wind penetration, or (c) the distance from the spinneret discharge surface to the point where air is sent by air cooling is shortened. Manufacturing method of dyed woven or knitted fabric.   When the false twisted yarn was dyed in a dyeing tank in which a blue hue test dye and a dispersant were dissolved in water and maintained at 95 ° C., and the periodicity of the dye density variation in the fiber axis direction of the yarn was measured with an FYL analyzer The method for producing a dyed woven or knitted fabric according to claim 1, wherein the maximum value in the wavelength range of 3 to 30 m of the power spectrum obtained by Fourier analysis of the digitized data is 25 [-] or less.   The method for producing a dyed woven or knitted fabric according to any one of claims 1 to 3, wherein a single fiber fineness of a filament constituting the false twisted yarn is 0.4 [dtex] or less.